We chatted with the creators and maintainers of four major projection systems, ZiPS (Dan Szymborski), Steamer (Jared Cross), THE BAT (Derek Carty) and Baseball Prospectus' PECOTA (Harry Pavlidis) about how their systems are created, how the past is used to project future performance and how projecting young players without much track record can be tricky.

Music is "Open Your Face" by Parker Projection.